.sand_u{
    width: 0;
    height: 0;
    margin: 8px auto;
    border: 64px solid transparent;
    border-bottom: 32px;
    border-top-color: green;
}
.sand_d{
    width: 0;
    height: 0;
    margin: 8px auto;
    border: 64px solid transparent;
    border-bottom: 32px;
    border-bottom-color: red;
}